Server-sent events (server-side)

We want to be able to receive updates through SSE.

There's a PR for servant-client adding support: https://github.com/haskell-servant/servant/pull/1317

But that appears to be just the client.

wai-extra seems to have some support: https://hackage.haskell.org/package/wai-extra-3.1.8/docs/Network-Wai-EventSource.html

https://stackoverflow.com/questions/37860770/servant-server-sent-events-support